Permanent magnet switch rotor control mechanism



H. G. DlETZ 3,165,605 PERMANENT MAGNET SWI TCH ROTOR CONTROL MECHANISM Jan. 12, 1965 Filed June 25, 1961 ArroeMF/ United States Patent "cc 3,165,605 PERMANENT MAGNET SWITCH ROTOR CONTROL MECHANISM Henry G. Dietz, Garden City, N.Y., assignor to Henry G. Dietz Co., Inc, Long Island City, N.Y., a corporation of New York Filed June 23, 1961, Ser. No. 119,143 9 Claims. (Cl. 200--81.9)

This invention relates to switch control mechanisms, and is primarily directed to an apparatus for controlling the operation of a snap-action switch, having a rotatable control shaft incorporated therewith.

It is particularly directed to a control mechanism for a snap-action switch, having permanent magnet control member attached to the rotatable shaft thereof, the switch control mechanism having a ferrite permanent magnet, or other'type of permanent magnet attached thereto, to control the rotation of the switch control shaft by magnetic attraction.

In operating a snap-action switch having a rotatable shaft control member attached thereto, it is necessary to have a control means which controls the rotational angular movement of the shaft and therefore the operation of the snap-action switch with a minimum of time delay.

In the conventional construction, either manual control means, or a mechanically actuated control mechanism is provided to rotate the rotatable switch shaft and therefore control the operation of the snap-action switch.

The primary. feature of applicants construction is that there is no direct physical contact between the rotatable shaft fitted to the snap-action switch and the control means, having a permanent magnet control member attached thereto, the operation being entirely magnetic.

Another feature of the construction is that magnetic lines of force provided by the ferrite permanent magnet, or other permanent magnet attached to the control member, are utilized to control the rotation of the switch control shaft and therefore the operation of the switch.

Another feature of the invention is that the control mechanism can be either a pivoted member or a recipro eating mechanism, which is movable into and out of the operating position.

Another feature of the invention is that it can be utilized in any medium such as air, a gaseous mixture, a liquid such as water, or any other fluid, which will allow magnetic lines of force to pass therethrough.

Another feature of the construction is that various components can be made of any required size to provide the necessary magnetic energy to rotatably control the 'permanent magnet attached to the rotatable switch control shaft. T z The accompanying drawings, illustrative of one em bodiment of the invention, and several modifications thereof, together with the description of their construction and the method of operation, actuation, and utilization thereof, will serve to clarify further objects and advantages of the invention; 1

In the drawings: 7

FIGURE 1 is a schematic vertical section through a valve fitted with a pivoted flapper, a micro-switch controlled by a rotating shaft having a permanent magnet attached thereto, being fitted to the valve, the valve flapper and the permanent magnet attached thereto being shown in the closed position of the valve.

FIGURE 2 is a schematic vertical section through the valve mechanism shown in FIGURE 1, with the hinged flapper shown in FIGURE 1, moved to the open position, away from the rotary permanent magnet attached to the switch control shaft.

FIGURE 3 is schematic cross-section through the valve, shown in FIGURE 1, and a plan view of the snap-action 3,165,605 Patented Jan. 12, 1965 permanent magnet being rotated to the free or switch deactivated position, corresponding to the open position of the flapper, shown in FIGURE 2, the view and section being taken on a line corresponding to the line 33, FIGURE 1.

FIGURE 5 is schematic front elevational view, similar to FIGURE 1, of a modification of the switch control mechanism, shown in FIGURE 1, the ferrite permanent magnet being attached to the lower end of the'flexible the magnetbeing attachedtothe hinged flapper by a bellows, which are shown in the expanded position, with the ferrite permanent magnet close to the rotary permanent magnet, the permanent magnet being rotated into the switch activating position, shown in FIGURE 3.

FIGURE 6 is a schematic front elevational view of the switch actuating mechanism shown in FIGURE 5, with the lower end of the bellows moved to the contracted position, with the ferrite permanent magnet moved a distance from the rotary permanent magnet, thereby allowing the rotary permanent magnet to reach the free or switch de-activated position, shown in FIGURE 4.

It will be understood that the following description of the construction and the method of operation and actuation of the permanent magnet actuated switch control mechanism is intended as explanatory of the invention and not restrictive thereof.

In the drawings, the same reference numerals designate the same parts throughout the various views, except where otherwise indicated.

2 One embodiment of the valve mechanism shown in material, such as Teflon, or other suitable light weight plastic material, is located within the central cavity 11,

the flapper being pivotally supported by-a pivot pin 17, which is fixedly attached to the body of the valve.

The lower face of the hinged flapper 10 has a ferrite, or other form of permanent magnet 19 attached thereto,

rivet 20,,or other suitable attaching means.

in the construction shown in FIGURES 1 and 2, the ferrite permanentmagnet is relatively thin, and of substantially rectangular cross-section in the plane of the face of the hinged flapper 16.

In controlling the angular movement of the flapper 16, from the closed position, shown in FIGURE l, to the open position shown in FIGURE 2, the fluid flows through:

the valve in the direction of the arrow 15.

A hollow cylindrical cavity 22 is formed at the lower end of the valve body, adjacent the angularly positioned bottom face 23 thereof.

A snap-action switch 24 having a rotatable control shaft 25 incorporated therewith, is mounted adjacent and 'attached to the angularly located bottom face 23 of the As shown in FIGURES 1 and 2, the hinged flapper 16 has a rivet, or stud 33 inserted therethrough, near the pivot pin 17, the stud 33 having a substantially cylindrical head 34integral therewith, the head having a substantially conical seat 35, through the upper face thereof.

, A substantially vertical secondary cylindrical passage 36 is cut through the body of the valve in substantially axial alignment with the conical seat 35 in the head 34 of the stud.

A substantially cylindrical flapper control plunger 37, having a substantially conical lower end 38 integral therewith, is located at substantially the center of the secondary passage 36 through the body of the valve.

An adjusting screw 40 having a slotted or other type of head 41 integral therewith, is threadably fitted to the threaded extension of the cylindrical secondary passage 36, through the valve body, the externally threaded body 4210f the adjusting screw being threadably fitted to the internally threaded upper end of the secondary passage 36. The threaded body 42 of the adjusting nut has a hollow central cavity 43 therein, the central cavity reciprocatingly supporting the spherical segmental upper end of the plunger 37. An O-ring 44, or other type of seal means, is located under the head 41 of the adjusting screw 40, the O-ring being fitted to a shallow counterbore in the upper end of the valve body 10, to seal the upper end of the secondary passage.

A coiled compression spring 45, surrounding the plunger 37, is inserted between the bottom surface of the threaded body 42 of the adjusting screw and the upper surface of a cylindrical collar 46, which is fixedly attached to the cylindrical plunger 37.

The conical tip 38 of the cylindrical plunger is seated in the conical seat, at the upper end of the head of the cylindrical stud 33, attached to the pivoted flapper.

The compression spring 45, by forcing. the plunger against the head 34'of the stud 33, controls the pressure against the pivoted flapper, thereby controlling the fluid pressure required to move the pivoted flapper from the closed position shown in FIGURE 1, to the open position shown in FIGURE 2. I

The normal operating length of the compression spring "45 is controlled by threadably adjusting the position of the body of the adjusting screw 40 against the compression spring 45, thereby controlling the pressure exerted by the toward the face of the rotary permanent magnet 26 being the center of the U, or the Neutral Area.

The poles designated S and N in FIGURES l and 2,

which are located at the ends of the face of the ferrite magnet 19 directed toward the rotary permanent magnet, represent the-North andSouth poles of the ferrite permanent magnet.

With the hinged flapper in the position shown in FIG- URE 1, the North pole (N), located at one end of the lower face of the ferrite permanent magnet 19, attached to the flapper 16, attracts the South pole (S) located at one side of the rotary permanent magnet, thereby causing the rotary permanent magnet 26 to be rotated to the angular position shown in FIGURE 3, thereby actuating snap-action switch 24.

In this position, the South and North (S and N) poles of the rotary permanent magnet are substantially aligned with the opposite poles, North and South (N, S) of the ferrite permanent magnet.

At the same time, the South pole (S) located at the lower face of the opposite end of the ferrite magnet 19 attracts the North pole (N) of the rotary permanent magnet, which is located diametrically opposite the South pole (S), thereby assisting in rotating the permanent magnet 26 and the rotatable shaft to which it is attached.

While shown moved through a rotational angle of approximately 45 from the inactivated position shown in FIGURE 4, to the actuated position shown in FIGURE 3, the actual rotary angular movement required to, actuate the snap-action switch 24 may be'a smaller angle.

With the flow of water, or other fluid in the direction of the arrow 15, the fluid impinges upon the bottom surface of the pivoted flapper, thereby causing the pivoted flapper to move through an angle to the position shown in. FIGURE 2. The angular movement of the pivoted flap-- per 16 from the position shown in FIGURE 1, to the position shownin FIGURE 2, is about 18".

When the pressure of the fluid moves the pivoted flapper 16 and the ferrite magnet attached thereto to the position shown in FIGURE 2, the magnetic lines of force between the poles of the two permanent magnets 19, 26 are broken, thereby allowing the rotatable permanent magnet to be restored to its free or inactivated position shown in FIGURE 4.

25 of the snap-action switch, shown in FIGURES 1, 3

and 4. Thus when the pull of the magnetic lines of force against South pole (S) of the rotatable permanent magnet is released, the rotatable permanent magnet assumes its free or switch inactivating postion, shown in FIGURE 4.

When the ferrite permanent magnet 19 shown in FIG- URES 1 and 2, is magnetized, the central portion of the magnet adjacent the rivet is the magnetically neutral portion. 2

One end of the bottom face of. the ferrite permanent magnet indicated as (N) in FIGURE 2, is the North pole. This corresponds to the postion ofthe point designated as S. on the rotatable permanent magnet 26, or the South pole (S) thereof, as shown in FIGURES 3 and 4. Thus, when the ferrite permanent magnet is in the position shown in FIGURE 1, with the ferrite magnet located close to the outer face of the rotatable permanent magnet, the North pole (N) of the ferrite permanent magnet at tracts the South pole (S) of the rotatable permanent magnet, thereby causing the rotatable. permanent magnet to move from the position shown in FIGURE 4, to the rotational angular position shown in FIGURE 3.

The bottom face of the opposite end of the ferrite.

permanent magnet is magnetized with the opposite. or South pole, designated (S) in FIGURES land 2. The

-- rotary permanent magnet is also magnetized in a manner similar to a U-shaped permanent magnet, with the center of the magnet the neutral point. The point designated (S) in the rotary permanent magnet shown in FIGURE 1,

, is magnetized as the South pole of the magnet. The point Normally, to actuate the snap-action switch, the face;

of the ferrite permanent magnet is located a distance of to from the outer surface of the rotatable permanent magnet, one pole, the North pole (N) of the ferrite permanent magnet attracting the opposite pole, the South (S) pole of the rotatable permanent magnet, thereby rotating the rotatable permanent magnet, thus causing the cylindrical shaft on which it is mounted to be moved to the switch actuating position shown in FIGURE 3.

At the same time, the South pole (S) of the ferrite permanent magnet 19 attracts the North pole (N) of the rotary permanent magnet 26. This distributes the load between the two poles of the ferrite permanent magnet 19.

When the ferrite permanent magnet is moved through a distance from the face of the rotatable permanent magnet 26 to the position shown in FIGURES 2 and 6, magnetic pull between the poles of the two permanent magnets 19, 26 is broken, thereby allowing the torsion spring surrounding the rotatable switch shaft 25 to restore the rotatable shaft to its free position, shown in FIGURE 4, thereby de-actvating the snap-action switch 24.

In a modification of the switch control mechanism, shown in FIGURES 5 and 6, expanding corrugated bellows 50 are substituted in place of the pivoted flapper shown in FIGURES 1 and 2.

A bottom plate 51 is attached to the lower end of the bellows, a ferrite, or other type of permanent magnet 52, similar to that shown in FIGURES 1 and 2, being attached to the bottom plate 51 of the bellows.

The upper end of the bellows 50 is supported by a tubular support member 53, a flanged bracket 54, the lower face of which is attached to the upper end of the bellows being fixedly attached to the tubular support member 53.

The tubular support member 53 is employed to withdraw a fluid from the interior of the bellows, thereby reducing the pressure within the bellows, and allowing the lower end of the bellows, with the ferrite permanent magnet 52 attached thereto, to be moved from the position shown in FIGURE 5, to the magnet release position shown in FIGURE 6.

A snap-action switch 55, similar to that shown in FIG- URES l, 4 and 5, is mounted below thepermanent magnet attached to' the bellows 50. The snap-action switch 55 has a rotatable control shaft 25 incorporated therewith, in the same manner as that shown in FIGURES l, 3 and 4.

A rotatable permanent magnet 26, made of Alnico, or other similar magnet material, is attached to the upper end of the rotatable shaft 25. The rotatable permanent magnet 26, shown in FIGURES 5, 3 and 4, has a central channel 29 cut therethrough, as shown in FIGURES 3, 4 and 5, the central channel 29 dividing the rotatable cylindrical permanent magnet 26 into two pole faces 30, 31, as shown in FIGURES 3 and 4.

As shown in FIGURE 5, the ferrite permanent magnet 19 has a North pole (N) at the bottom face of the magnet near. one end 21 thereof, and a South pole (S) formed at the bottom face of the magnet near the other end thereof. In the same manner, the rotatable cylindrical permanent magnet 26 is so magnetized that the central area of net, adjacent the channel 29, is the neutral. area of therot atabie permanent magnet, a South pole (S); being located adjacent the outer circumference ofthe rotatable permanent magnet, near one edge of the central channel 29 at the point indicated in FIGURE 3. I The North pole (N) of the rotarypermanent magnet is located diametrically opposite the South (S) pole thereof, adjacent the opposite edge of the channel 29.

When the ferrite permanent'magnet is located in the position shown in FIGURE 6, with the face'thereof a considerable distance from the face of the rotatable switch magnet 26, the rotatable permanentmagnet 26 attached to the shaft of the switch, assumes the position shown in FIGURE 4,which is substantially the same as that assumed by the rotatable permanent magnet, when 6.. the pivoted flapper 16 is in the position shown in FIG- URE 2.

This is due to the pull of the magnetic lines of force of the North pole (N) of the ferrite permanent magnet, which attracts the South pole (S) of the rotary permanent magnet, thereby reducing the distance, and therefore the air gap between the opposite magnetic poles of the two magnets.

Thepull of the opposite or South pole (S), which attracts the North pole (N) of the rotary permanent magnet is substantially equal to that of the North pole, thereby distributing the load over the two poles.

The operation of the switch control mechanism, shown in FIGURES 5 and 6, is substantially the same as that shown in FIGURES 1 and 2. d

When the bellows are in the extended position, shown in FIGURE 5, the North pole (N) of the ferrite permanent magnet 52 attracts the South pole (S) of the rotary permanent magnet, thereby drawing the rotary pennanent magnet to the rotational angular position, shown in FIGURE 3, and in that manner activating the snap-action switch 55.

At the same time, the South pole (S) of the ferrite permanent magnet 52, attracts the opposite pole (N) of the rotary permanent magnet, thereby assisting in rotating the permanent magnet 26.

When the fluid pressure in the bellows50 is reduced, the bellows are contracted, the lower end of the bellows and the ferrite magnet 52 attached thereto being moved to the position shown in FIGURE 6, with the North and South poles '(N), (S) of the ferrite permanent magnet located a considerable distance, approximately 1 inch, from the opposite poles of the rotary permanent magnet 26. This releases the magnetic pull between the ferrite permanent magnet 52 and the rotary permanent magnet 26, thereby allowing the torsion spring surrounding the rotatableshaft 25 of the snap-action switch to restore the rotatable shaft and the permanent magnet 26 attached to the shaft to the inactivated, or free position shown in FIGURE 4, the snap-action switch being inactivated. While the bellows 50 in the construction shown in FIGURES 5 and 6, are controlled by the flow of fluid under pressure fluid in the interior of the bellows, the bellows may be actuated by gas pressure fed internally or a gas filled, externally fluid operated bellows may be subtituted.

In place of the construction shown in FIGURES 1 and 2, or the modified construction shown in FIGURES 5 and 6, other types of apparatus for converting linear motion to rotary motion in a plane perpendicular to the axis of the linear motion may be substituted.

Thus any type of linearly movable mechanism with a ferrite permanent magnet, such as that shown in FIG- URES Sand 6 incorporated therewith, may be substituted for the bellows, shown in FIGURES 5 and 6.

In. place of the switch control mechanism shown in FIGURES 5 and 6, any other type of rotary shaft, with a rotatablepermanent magnet, such as that shownin FIGURES Sand 6, attached thereto, may be substituted. A torsion spring would be attached to the rotary shaftto restore it to the free position shown in FIGURE 4, when the magnetic pull is released. v

Instead of the switch, anindicator arm would be attached to the rotary shaft, the indicator arm being utilized in conjunction with a dial having radial angle graduations, to indicate the angular displacement of the rotary permanent magnet and the shaft on which it is mounted,

displaced position shown 6, any other suitable mechanism may be substituted, to

draw the ferrite magnet from the operating position, with the face and pole of the ferrite magnet close to the face and opposite pole of the rotary permanent magnet, to a position similar to that shown in FIGURE 6, with the ferrrite magnet located a consideiable distance from the face of the rotary permanent magnet 26, thereby allowing the rotary permanent magnet to be restored to its free position, with the snap-action switch inactivated.

While the apparatus shown in FIGURES 1 and 2, is shown used in conjunction with a fluid-controlled valve, other types of flapper control mechanism may be substituted to draw the flapper 16 with the ferrite magnet attached thereto, from the switch activating position shown in FIGURE 1, to the free or release position shown in FIGURE 2.

In place of the pivoted flapper supporting the ferrite permanent magnet, as shown in FIGURES 1 and 2, any other suitable magnet support means may be substituted, the essential feature of the construction being that in the switch activating position, the ferrite permanent magnet 19 is located close to and substantially parallel to the face of the rotary permanent magnet, with opposite poles of both magnets located close to one another, whereas in the magnet release position shown in FIGURES 2 and 6, the ferrite magnet is moved to a distance from the face of the rotary permanent magnet, to break the magnetic pull between the two-permanent magnets 19 and 26.

While the ferrite permanent magnet shown in -FIGURES 1 and 5, is shown as a relatively flat permanent magnet of rectangular contour, the cross-sectional contour of the ferrite magnet may be varied considerably, the essential feature of the construction being the relation between the North pole (N) of the ferrite magnet 19 and the South pole (S) of the rotary permanent magnet.

While as shown in the drawing, and described hereinbefore, the North pole (N) of the ferrite magnet is used I in conjunction with the South pole (S) ofthe rotary permanent magnet 26, these can be reversed, the South pole (S) of the ferrite permanent'magnet 19 being used in conjunction with the North pole (N) of the rotarypermanent magnet.

While described as a ferrite magnet, the permanent magnet 19 attached to the flapper in the construction shown in FIGURE 1, or attached to the lower end of the bellows 50, as shown in FIGURES 5 and 6, any other type of permanent magnet, such as an Alnico magnet, may be substituted for the ferrite magnet, the essential feature being that the magnetic lines of force provided by the permanent magnet 19 must be adequate to attract mounted within the snap-action switch;

It will be apparent to those skilled in the art that the present invention is not limited to the specific details I described above and shown in the drawings, and that various modifications are possible in carrying out the features of the invention and the operation, actuation, and method of utilization thereof, without departing from the spirit and scope of the appended claims.

What is claimed is:

1. A permanent magnet control mechanism, comprising a rotatable shaft, a first substantially cylindrical permanent magnet having one relatively flat face, fixedly attached to the rotatable shaft, a second. relatively flatfaced permanent magnet mounted in a position in which the flat face of the second permanent magnet is movable to a position close to the fact of the first permanent magnet, a flapper of a nonmagnetic material fixedly attached to the second permanent magnet, means pivotally supporting one end of the nonmagnetic flapper supporting the second permanent magnet, said flapper being operative to move the second permanent magnet to a predetermined distance from the face of the first permanent magnet, the second permanent magnet being so magnetized'that the magnetic poles thereof are formed on the face thereof directed toward the first permanent magnet, the first permanent magnet being magnetized so that the magnetic poles thereof are strongest on the face thereof di rected toward the second permanent magnet, a coiled torsion spring surrounding the rotatable shaft, one end of said torsion spring being attached to the rotatable shaft, said torsion spring being operative to normally retain the rotatable shaft in a rotational position in whichthe poles of the first permanent magnet are out of alignment with the opposite poles of the second permanent magnet, the first permanent magnet being rotated into a position in which the poles thereof are substantially aligned with the opposite poles of the second permanent magnet, when the second permanent magnet is moved to a position with the magnetic pole face thereof close to the face of the first permanent magnet.

2. A permanent magnet control mechanism, as in claim 1, in which the second permanent magnet is a ferrite permanent magnet. I

3. A permanent magnet control mechinism, as in claim 1, in which the rotatable shaft is supported by a snap- -acti on switch, said snap-action switch being in an inactivated position, when the poles of the first peirnanent magnet are angularly disposed, relative to the poles of the second permanent'magnet, a torsion spring fitted to and supported by the rotatable shaft, the shaft supporting the first permanent magnet being adapted to activatev the snap-action switch when the first permanent magnet is rotated into a position in which the poles thereof are substantially aligned with opposite poles of the second permanent magnet.

4. A valve control mechanism, comprising a hollow valve housing, having inlet and outlet passages therethrough, a fluid passing through the hollow housing, an I angularly movable flapper of a non-magnetic'material, mounted Within the housing, means fixedly attached to the hollow housing pivotally supporting the flapper, a first relatively flat permanent magnet fixedly attached to one face of the flapper, a rotatable shaft supported within the housing substantially perpendicular to one face of the pivoted flapper, a second substantially cylindrical rotatable permanent magnet fixedly attached to the rotatable shaft,

said second rotatable permanent magnet having a rela- I tively flat face directed toward'one face of the first permanent magnet attached to the flapper, the first permanent magnet being so magnetized that the magnetic poles thereof are formed on the face of the magnet directed toward the second permanent magnet, thesecond permanent magnot being so magnetized that the magnetic poles thereof are strongest in the face thereof directed toward the first permanent magnet, a coiled torsion spring fitted to the rotatable shaft supporting the second permanent magnet one end of said tension'spring being fixedly attached to is located in a position in which the face of the first permanentmagnet is close'to the face of the second permanent magnet the second permanent magnet being rotated into a posit on, in which the poles thereof are substantially Q aligned with the opposite poles of the first permanent magnet.

6. A valve control mechanism, as in claim 4, in which the rotatable shaft is supported by a snap-action switch, the snap-action switch being attached to one face of the hollow housing, the rotatable shaft being adapted to deactivate the snap-action switch when the pivoted flapper is angularly displaced to a position in which the face of the first permanent magnet is located at a distance from the face of the second rotatable permanent magnet, the torsion spring and fitted to the rotatable shaft rotating the shaft and the second permanent magnet attached thereto into the switch deactivating position, when the magnetic pull between the first and second permanent magnets is released, the fluid passing through the valve housing being adapted to engage one face of the flapper and the first permanent magnet attached thereto, to move the first permanent magnet into a position at a predetermined distance from the face of the second permanent magnet.

7. A valve control mechanism, as in claim 4, in which the first permanent magnet attached to the flapper is a ferrite permanent magnet, the rotatable shaft being supported by a snap-action switch, the snap-action switch being attached to one face of the hollow housing, the rotatable shaft being adapted to activate the snap-action switch when the pivoted flapper is located in a position in which the face of the first permanent magnet is close to and substantially parallel to the face of the second rotatable permanent magnet, the magnetic pull of the first permanent magnet against the poles of the second permanent magnet being adapted to rotatably angularly displace the second permanent magnet and the shaft to which it is attached, the poles of the second permanent magnet being substantially aligned with the opposite poles of the first permanent magnet in the angularly displaced position, the 3 t0 the face of the pivoted flapper, and the first permanent magnet attached thereto.

8. A valve control mechanism, as in claim 4, in which the first permanent magnet is a ferrite permanent magnet, the ferrite permanent magnet being magnetized in substantially the same manner as a U-shaped permanent magnet, the N and S magnetic poles of the first permanent magnet being of maximum strength adjacent the ends of the face of the first permanent magnet directed toward the face of the second permanent magnet.

9. A valve control mechanism, as in claim 4, in which the first permanent magnet is a ferrite permanent magnet, the second permanent magnet at the face of the magnet directed toward the first permanent magnet having a slot therethrough, the slot dividing the face of the second permanent magnet into two sections, the second permanent magnet being magnetized in substantially the same manner as U-shaped permanent magnet, the N and S poles of the second permanent magnet being of maximum magnetic strength at the face of the second permanent magnet directed toward the first permanent magnet.

References Cited by the Examiner UNITED STATES PATENTS 1,917,317 7/33 Nacey 20087 2,352,830 7/44 Ford ZOO-87 2,448,779 9/48 Crise 200-37 2,548,581 4/51 Bigelow 200-67 2,620,412 12/52 Ford 20084 2,822,442 2/ 58 Jones 20O84 2,915,606 12/59 Kiyauth 200-87 3,073,919 1/63 Holder 20087 5 BERNARD A. GILHEANY, Primary Examiner.

WALTER STOLWEIN, Examiner. 

1. A PERMANENT MAGNET CONTROL MECHANISM, COMPRISING A ROTATABLE SHAFT, A FIRST SUBSTANTIALLY CYLINDRICAL PERMANENT MAGNET HAVING ONE RELATIVELY FLAT FACE, FIXEDLY ATTACHED TO THE ROTATABLE SHAFT, A SECOND RELATIVELT FLATFACED PERMANENT MAGNET MOUNTED IN A POSITION IN WHICH THE FLAT FACE OF THE SECOND PERMANENT MAGNET IS MOVABLE TO A POSITION CLOSE TO THE FACT OF THE FIRST PERMANENT MAGNET, A FLAPPER OF A NONMAGNETIC MATERIAL FIXEDLY ATTACHED TO THE SECOND PERMANENT MAGNET, MEANS PIVOTALLY SUPPORTING ONE END OF THE NONMAGNETIC FLAPPER SUPPORTING THE SECOND PERMANENT MAGNET, SAID FLAPPER BEING OPERATIVE TO MOVE THE SECOND PERMANENT MAGNET TO A PREDETERMINED DISTANCE FROM THE FACE OF THE FIRST PERMANENT MAGNET THE SECOND PERMANENT MAGNET BEING SO MAGNETIZED THAT THE MAGNETIC POLES THEREOF ARE FORMED ON THE FACE THEREOF DIRECTED TOWARD THE FIRST PERMANENT MAGNET, THE FIRST PERMANENT MAGNET BEING MAGNETIZED SO THAT THE MAGNETIC POLES THEREOF ARE STRONGEST ON THE FACE THEREOF DIRECTED TOWARD THE SECOND PERMANENT MAGNET, A COILED TORSION SPRING SURROUNDING THE ROTATABLE SHAFT, ONE END OF SAID TORSION SPRING BEING ATTACHED TO THE ROTATABLE SHAFT, SAID TORSION SPRING BEING OPERATIVE TO NORMALLY RETAIN THE ROTATABLE SHAFT IN A ROTATIONAL POSITION WHICH THE POLES OF THE FIRST PERMANENT MAGNET ARE OUT OF ALIGNMENT WITH THE OPPOSITE POLES OF THE SECOND PERMANENT MAGNET, THE FIRST PERMANENT MAGNET BEING ROTATED INTO A POSITION IN WHICH THE POLES THEREOF ARE SUBSTANTIALLY ALIGNED WITH THE OPPOSITE POLES OF THE SECOND PERMANENT MAGNET, WHEN THE SECOND PERMANENT MAGNET IS MOVED TO A POSITION WITH THE MAGNETIC POLE FACE THEREOF CLOSE TO THE FACE OF THE FIRST PERMANENT MAGNET. 